Improve inspection and generation of node keys (#11525)

* Improve inspection and generation of node keys

* Lock stdout before write

* Fix typo

* Fix offset

* Remove useless code

* Set inspect-node-key 'network' option as obsolete

substrate/bin/utils/subkey/src/lib.rs

@@ -30,8 +30,8 @@ use sc_cli::{
 	version
 )]
 pub enum Subkey {
-	/// Generate a random node libp2p key, save it to file or print it to stdout
-	/// and print its peer ID to stderr.
+	/// Generate a random node key, write it to a file or stdout and write the
+	/// corresponding peer-id to stderr
 	GenerateNodeKey(GenerateNodeKeyCmd),
 
 	/// Generate a random account
@@ -40,7 +40,7 @@ pub enum Subkey {
 	/// Gets a public key and a SS58 address from the provided Secret URI
 	Inspect(InspectKeyCmd),
 
-	/// Print the peer ID corresponding to the node key in the given file
+	/// Load a node key from a file or stdin and print the corresponding peer-id
 	InspectNodeKey(InspectNodeKeyCmd),
 
 	/// Sign a message, with a given (secret) key.